Gfs Overview; Performance, Scalability, And Economy; Superior Performance And Scalability; Gfs Functions - Red Hat ENTERPRISE LINUX 4 - GLOBAL FILE SYTEM Manual

Chapter 1.

GFS Overview

Red Hat GFS is a cluster file system that is available with Red Hat Cluster Suite. Red Hat GFS nodes
are configured and managed with Red Hat Cluster Suite configuration and management tools. Red
Hat GFS provides data sharing among GFS nodes in a Red Hat cluster. GFS provides a single,
consistent view of the file-system name space across the GFS nodes in a Red Hat cluster. GFS allows
applications to install and run without much knowledge of the underlying storage infrastructure. GFS
is fully compliant with the IEEE POSIX interface, allowing applications to perform file operations as
if they were running on a local file system. Also, GFS provides features that are typically required in
enterprise environments, such as quotas, multiple journals, and multipath support.
GFS provides a versatile method of networking your storage according to the performance, scalability,
and economic needs of your storage environment. This chapter provides some very basic, abbreviated
information as background to help you understand GFS. It contains the following sections:
Section 1.1, "Performance, Scalability, and Economy"
•
Section 1.2, "GFS Functions"
•
Section 1.3, "GFS Software Subsystems"
•
Section 1.4, "Before Setting Up GFS"
•

1.1. Performance, Scalability, and Economy

You can deploy GFS in a variety of configurations to suit your needs for performance, scalability, and
economy. For superior performance and scalability, you can deploy GFS in a cluster that is connected
directly to a SAN. For more economical needs, you can deploy GFS in a cluster that is connected to a
LAN with servers that use GNBD (Global Network Block Device).
The following sections provide examples of how GFS can be deployed to suit your needs for
performance, scalability, and economy:
Section 1.1.1, "Superior Performance and Scalability"
•
Section 1.1.2, "Performance, Scalability, Moderate Price"
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Section 1.1.3, "Economy and Performance"
•
Note
The deployment examples in this chapter reflect basic configurations; your needs might
require a combination of configurations shown in the examples.

1.1.1. Superior Performance and Scalability

You can obtain the highest shared-file performance when applications access storage directly. The
GFS SAN configuration in
files and file systems. Linux applications run directly on GFS nodes. Without file protocols or storage
servers to slow data access, performance is similar to individual Linux servers with directly connected
storage; yet, each GFS application node has equal access to all data files. GFS supports up to 16
GFS nodes.
Figure 1.1, "GFS with a SAN"
provides superior file performance for shared
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